Axisymmetrical components, such as an axisymmetrical component 100 that is shown in FIG. 10 and symmetrical around a central axis 101, have been used in various machines. The axisymmetrical component 100 may include a tapered portion 110 and a flange portion 120 projecting inward from a large-diameter portion of the tapered portion 110. One example of the axisymmetrical component 100 is an aircraft component. As one example of such aircraft component, FIGS. 2 and 3 of PTL 1 disclose a rear annular inner passage wall (part shown by reference sign 72) used in a gas turbine engine of an aircraft (PTL 2 will be described later).